Signaling and interlocking system for traffic routes



July 1 1941- G. l.. cAlLLE ETAL 2,247,801

SIGNALING AND INTERLOCKING SYSTEM FOR TRAFFIC ROUTES4 Filed July 26, A1959 l0 Sheets-Sheet 1 59./ 242.@2@ ,wv/4 I /K @/2@ 5,4m 5 5,14 @A2 ZD C J 3 c Q FF) C 2817/ I O O Ju1y1,1941. G. L. CAME ET AL 2,247,801

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SIGNALI-NG AND INTERLOCKING SYSTEM FOR TRAFFIC ROUTE-S Filed July 2e. 1959 1o sheets-sheet s c 2ER .aug .sul as als 6-89 HR Hg' 5B 7 z wm DC SWS/felle arz Gea/ges Lamis Caille and I [NVE/VTHSA/lexandpp .Pw/pe Laze. 7gg@ A7703 V51/j July 1, 1941. G. L. CAILLE ETAL SIGNALING AND INTERLOCKING SYSTEM FOR TRAFFIC ROUTES Filed July 26. 1939 2c me c .arf m 55m as al l wie c c @fm E@ IAM v .5.0

Geo/yesLauzls Sadlecmd Tlf/WA ATTORNEY- 10 Sheets-Sheet 5 July 1, 1941. 6.1. CAILLE ETA. 2,247,801Y SIGNALING AND NTERLOCKING SYSTEM FOR TRAFFIC ROUTES y Filed Juiy .26. 1959 1o sheets-sheet e snr c I 242x 411e In mf A lJuly 1, 1941- G. L cAlLLE Erm. 2,247,801

SIGNALING AND INTERLOCKING SYSTEM FOR TRAFFIC ROUTES Filed July 2e. 1939 1o sheets-sheet 7 VPF l/vws /ws 5 i 5mn/s sfews l-c- E Uw I 1 r 5L@ I F 'im-ifi@ sew-#BM i l I `scp ecp 6A@ 6005 @e 4LMP `401 4//2 460.5

mimATmH/VY July 1, 1941 G. L cAlLLE x-:TAL v 2242801 SGNALING AND INTERLOCKING `SYSTEM FOR TRAFFIC ROUTES Filed July 26, 1939 10 Sheets-Sheet 8 Hg f6.

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SIGNALING AND INTERLOCKING SYSTEM FOR TRAFFIC ROUTES Filed July 2e. 1959 1o sheets-sheet 9 @w cu @LP c cil-lfd am @ca aaaa T] '321% el@ 3:@

4m: 4M 4ax am: sia sar ma lara /aaf 34a sa@ am aap Alexanrd/e Pulp/@Mza THE/TTRNEK Patented July 1, 1941 UNITED" STATES SIGNALING AND' INTEBL'OCKINGSYSTEM' FOR'TRAFFIC ROUTES Georges` LouisA Caille, Vaujours, vand Alexandre Pierre Laze, Paris, France, .assignors, by mesne assignments, to vThe Union.. Switch &, Signall Company, Sw'ssvale, Par, a'corpora'tionof Penn- Sylvania Application. 1111x726, 1939seria1310,286,663. In France January 14, 1939 33 Claims. (nel. 24e- 134)j A number of railway-signaling. andinterlocking: systems are already known, which. are for the purpose of controlling traflicmovementsthrough a track layout comprising. track sections, inter- A' routeLrelays` has the advantage thatv in,y the` case of; the common, return wires4 being broken the two windings. of theV relay produce opp()siteuXeS,

thereby preventing undesired operation. in,r the,

connected by track switches adaptedtovbe placed gcase. of.' a fault. f

in dilerent positions so as to form differenttraffic. routes.

There is particularly one known arrangement which is characterized by the. use ofindividual control members both for the entrance an-dfon 10j signal to this route is in its stop, position,

the exit end of each route considered. The ,pres ent invention relates to apparatus of thisY character which, however, is distinguished? from the previously known arrangement referred to by the following features: f

The establishment of a routev is effected by. means of a single contact device (button, lever, or the like) and by means of a singlevoperation. This route is automatically cancelled lby the passage of a train through this route. Y Certain of the routes which can be establishedby the apparatus can be rendered permanent if desired and are further arranged in such amanner as to remain established after the passageI Thearrangement adopted'permitsa s implication of the interlocking system owingntor, the pro-Y vision of meansfor insuring that the preparation ofr a route can be initiatedonly-when theentrance` In orderA to simplify, theY diagrams, a track crossing withoututrack switches has not been illustrated, but it is to be understood that this is equivalent to 'a track-f switch in respect to the interlocking 1.5i required; Furthermore, the clearing of. a signal issubject tothe checking of the switch locking.

In View ot these various objects and further; objects whichwill appear as the detailed description proceedathe invention thus consists in thev 2.0; arrangement as a, whole and in the details-of, the

electric circuitsY andapparatus, in the arrange,- rnent and .operation of, the control desk, and ofthe miniature track diagram-combined therewith, and. also in the various arrangements provided for of a train through one of these permanent. routes. obtaining the,- various features herein described.

In the case of failure of a track circuit, swithf locking may be temporarily cancelledV so as, to allowV during this period Vthe operationofgthe track switch in the defective section from the central control ollce. v Y' The interlocking control system of our. invention is further arranged to provide sectional-route locking. of an improved typecharacterized bythe locking of the track switches front vand the release at the rear yofY each train, even thoillg-:liy 35;

the train passesthe entering signal at stop.- Y .A

The interlocking control system. of ourvinvention comprises, in addition to the usual track circuits and signals andv associated; control and indication relays, an'operatorspanel placed ata 4D.:

central oice and provided With an assembly of route `control devices combined with an illuminated track diagram constituting a miniature representation of the controlled tracks, the signals and track switches,A as well as the other ap- 45.

paratus interlocked with the same and vcontrolled from this ofjce. The essential feature-of Vthe route control system consists in the use of a single route relay of the polar type or preferably: ofthe typev having two windings with a commoneturn 50 Wire for each route, each of these windingsr corresponding to one of the two possible directions of traffic movement over theroute, the'direction of traicmovement being determined byza signal Qur invention isanA improvement uponl that4 disclosed tin the French Patent No. 829,857; v0L November 24, 1937, which correspon-ds to. the United` States applicationL Serial. No. 118,609',A filed December 31, 1936, by John M. Pelikan, for Rail,- vvayv traiccontrolling apparatus.

Inv order that the invention. should be readily, understood, one embodiment thereof willnow. be described with certain modifications, as illustrated in the accompanying drawings in which Figs.l 1 to *21, inclusive, taken together, illustrate diagrammatically the circuits and apparatus for. a. route interlocking system embodying one form of our invention, While Figs. 5A and 5B. illustrate modiiications. Moreparticularly, Eig, l, is.. a schematic diagram of` a system of tracks, track switches` and signals, constituting a miniature representation of thetracklayout chosen. to illus,- trate our invention, which. diagram is placed in thev control office to be controlled by the signaling and route' interlocking systems according' to:A the invention;

Fig. 2 shows schematically the frontof. the control desk with thevariousbuttons P groupedand arranged according` to a plan, which Will be specified hereinafter;

' Fig. 3; shows likewiseschematically the-arrangement. of the buttons AP for effecting the emergency. release of the detector locking control"relayfY vThe I ,Jr'cvisi,on r of vdouble winding 5,5 v Fig.4 shows' in itsupper portion, a track plan illustrating the arrangement of the tracks of the layout to be controlled, together with the circuits for the track relays TR and repeating relays controlled thereby, and in its lower portion, the circuits for the switch control relays WR, the switch indication relays WP and the switch locking relays LR;

Fig. shows a route circuit network comprising the circuits for the route relays R and the signal control relays HR controlled by the buttons P of Fig. 2;

Figs. 5A and 5B show two alternative forms of the route circuit network, either of which may be used in place of that of Fig. 5 in the system of Figs. 1 to 21, inclusive;

Fig. 6 shows the signal circuit network comprising the circuits for the signal relays G and for the call-on signals M;

Fig. 7 shows the circuits for certain auxiliary route relays NR and RR;

Fig. 8 shows the circuits for a group of directionally controlled indication relays ESK. and WSK for controlling the lighting of the track diagram;

Fig. 9 shows the circuits of the approach locklng relays LS and the time element relays TE associated therewith; Y Fig. 10 shows the circuits for the section locking relays ES and WS, for effecting the sectional release of the route locking;

Fig. 11 shows the circuits for the emergency release relays A controlled by the buttons AP of Fig. 3; Y

Fig. 12 shows schematically the internal circuits of the double-winding route relays of Fig. 5 or 5A, to illustrate their operation in the case of the common return wires being broken;

Fig. 13 shows apparatus for operating the track switches individually, comprising the normal andreverse switch stick relays NWS and RWS controlled by the buttons NP and RP of Fig. 2;

Fig. 14 shows the circuits for the call-on stick relays COS controlled by the buttons CP of Fig. 2;

' Fig.'15 shows the circuits for the red and green signal indication lamps which are placed at the corresponding signal locations in Fig. 1;

Fig. V16 shows the circuits for the red and white lamps for illuminating the track portions of Fig. 1;

Fig. 17 shows the circuit for a relay E, by means of which the switch indication lamps of Fig. 16 may be lighted checking the position of the track switches;

Fig. 18 shows schematically the lighting circuits of the various signals provided along the tracks of Fig. 4;

Fig. 19 shows the circuits for the signal indication relays GP and MP; and

Figs. 20 and 2l show a vertical and horizontal section respectively of a particularly advantageous arrangement of the elements of the illuminated track diagram of Fig. 1, permitting a reduction in the space required by these elements and facilitating the replacement of the lamps thereof.

Similar reference characters refer to similar parts in each of the several views.

According to the current practice in signaling systems, the track switches are identified by odd numbers i, 3, 5, whereas the track signals are identified by even numbers such as 2, 4, 6, 8, the corresponding numbers being repeated on the operators panel of Fig. 2 and on the track diagram of Fig. 1. The two switches of a crossover have the same numbers, and are differentiated by suxes A and B, and the same is the case in respect to multiple-light or multiple-arm signals.

In this connection it should be noticed that the diagrams, (see Fig. 4) indicate multiple-light signals but it is obvious that multiple-ann signals performing the same functions could also be employed.

In the various circuit diagrams each relay is 10- identied by a letter or a combination of letters j which it is controlled. Furthermore, instead of preceded by the designation of the track switch or the signal with which this relay is associated.

The numbers identifying the switches and signals are also employed to identify the push buttons and route relays associated with particular routes; for example, the designation 4-81P indicates that the button bearing this designation governs the route from signal 4 to signal 8 via the crossover switches iB and IA reversed, while the designation 4-85R indicates that the route relay bearing this designation is associated with route 4 8 via 5 reversed.

Furthermore, in order to facilitate the identii'lcation of the direction of trafc movements and of the routes governed by particular signals, the destinations of all the routes of Fig. 4 have been respectively designated by A, B, C, and D, E, these characteristic letters being then utilized in the diagrams for distinguishing the signal relays,

such, for example, as the relay 4EG for the route extending from signal 4 to the point E.

In order tofacilitate the reading of circuits, the same are dealt with in the description with similar circuits grouped in the same gure. In the circuits as shown the relay contacts are not necessarily adjacent the relay by which they are controlled, and a contact is identified not only by a reference character comprising a number, but more particularly by mentioning the relay by illustrating the local source of current from which the relays are energized, only the supply wires indicated by the references B and C have been illustrated, which respectively correspond to the positive or supply wire and to the negative or common return wire of the'source.

As shown in Figs. 1, 2 and 3, the operators panel proper comprises an illuminated track diagram (Fig. 1), a control desk (Fig. 2) and an auxiliary panel (Fig. 3). The miniature track diagram of Fig. 1 `comprises translucent sections representing the various track sections interconnected by the track switches, which can be selectively illuminated by lamps placed at the back of the panel (Figs. 20 and 21), the lamps being energized in accordance with the position of the contacts of the relays which control them (Figs. 15 and 16) Owing to the arrangements used, the control desk of Fig. 2 may be made in very small dimensions and consequently may be disposed in the most suitable manner relative to the track diagram or may be arranged to form a single unit together with the latter.

` As indicated in the figure, this desk comprises a certain number of vertical columns of buttons, l above yWhich'a horizontal row is arranged. The route Ibuttons are located in the vertical columns below the word Exit, the route buttons in each column being those associated with routes having the same entrance. VEach route button bears a number, such as 2, 4, 6, 8, I0, etc. According to the principal feature of the invention there is only a single button vforeach route and the number carried by the button corresponds to the destination of this route. For preparing a route it isv only necessary for the signalmanto press the. corresponding butto-n. without having to effect any further operation.. The simplcation of the control is still increased owing to the fact that the buttons for the various routes havingthe same entrance. are grouped in. vertical columns. It will thus be seen that the buttons 2-...8P and 2-.-I 2B, for example, marked 8 and I2 andlocated ink therst vertical column (entrance Dagovern routesZ-:a and 2-I12, respectively1 Each vertical column. includesfurther a route cancellingpull fbuttonlZA'np, IIAnp... IIlAnp. The desk further comprises a set of call-on press buttons 4CP, GCP., SCP, theseV buttons being provided for each entran-ce yat which the associated signal is provided, with a call-onlight orfarm.

Certain. of the columnsl comprise direct` route buttons such. as. 2'. 8DP., IUIIDR the.v operation ofwhich will ybedescri-bed further below.

Finally, an. emergency switch ndicationpress buttonv EP. permits theswitch indicating portions of the track diagram to beilluminated at will, the trackdiagram being normally dark andthe portionscorresponding to a routebeing illuminated automatically onlyy when the nouteisset upY or is` occupied bya train. The provisionfoi` .button El?. allows the.signalman-.to ascertainaat anytimethe position of each of the. track switches. They il-v lumination is extinguished when this lbuttonisreleased. Finally, the. upper.a row of:y buttons NP and. RP.; permits when necessary the control of the track switches individually, particularlywhen a track circuit has become defective. y

It should be notedin connection therewiththat. the. indiyidualy control of the-..track switches iseffectedinY a mannerl which, is 'alreadyv known and described in the French patent hereinbefore. referred to, and accordingly itfvv-ill notbe Vdescribed indetail.

The. various functions stated.v hereinafter,

namely: y Y f .Ereparation of a route,

Cancellingof a route,

Call-on operation, .2.5.1 Establishment of a direct or permanent route, are,h-ereinafter describedindividually and in de.- tail, first as regards their `operation and the efe. fects, resulting therefrom.- and. then.-as.regards th circuits themselves.

The. auxiliary panel schematicallyv illustrated. in.. Fig. 3, which isiplaced adjacent'. the control desk, Aand which, ifnecessary may bevsealed, is4 provided for permitting. thecancelling of thecdee tector switch locking by the operation of section-. cancelling pressybuttons` IAP SAP provided ina number equal to that ofthe trackcircuits. Thebperation of this panel is. as follows;

When for anyreaspna track relay. isnot energiaedwhen its sectionis unoccupied, one or more.

associated track switches would be lockedwhich. would prevent the establishment of certain routes; with.` the` present .apparatus the signale man` may. press the cancellingbutton corresponding to the defective. track section and then operate theV switch -or switches; by anindividual con. trolgdevice. to the desired position, and thenprepare-the route in the usual manner.v

- Inthe event. that. theentrance signal does not gno.. to .,proceed the operator may. authorize. the passage. of the .train over the route.;v

(a) By giving a direct or permanent route, if possible, the route circuits and signal-circuitsI for these routes, being independent.oi.7 track circuit;

canal-lions:

(-b) By displaying the call-on light or arm when it is provided, or by issuing apermit in the -case Where neither a permanent route signal nor a call-on signalis available.

'Ihe cancelling of the switch locking for a sec-- tion is automatically nullied by thev operation of thej route button for a, route which includes. the

section, The operation of. the cancelling b utton will thushave to be repeated each time. that the4 operation ci a locked track switch is neces- Sary..

. 'rhejyariousz operations. which may Ibe carried out, with the apparatus4 described and illustrated in Figsl to` 3r will now be described in detail with reference tothe detailed circuits of Figs. 4 tov 19.

Establishment of nonfpermanent route-As.- sumrng that a. route is to be established from 4 to 8; vial rerersed. it is only necessary for the Sisnalman toA press. the. button, 4-81P. which in Eig.. 2: is.: marked. 8.1 and is. located in thev column Entrance 4i, and thus to produce the following operations (see lig. 5)f:r

The route relay 4.-8.1R; (Fig, 5) is energized by acircuit comprising Wire B, front Contact 16.1

,. of. relay: 5LB, front. contacts |62 of. relay 2LS. front contact |613 of. relay 4LS. front contact. |64

of; Qressbulton lli-QP, back Contact 1.6.5 of relay 2- 81B.-, winding oif'relay'II-BlR and return` wire C.

The energized relay. 4-81R completes the picklll?.- oircuit for relay ll-IZRV comprising wire. B.

front Contact l of` relay SLR, front Contact |68 of relay frontl contact 9 o f relay 4LS, front Contact |10. of. relay BLS. front Contact H of relay Gp-8,112.1, back Contact |52` of relay 498512.,

,1 back; Contact |53;l of; relay -IUR. winding of re.-

lay 1 -IER, and return wire C. The energization of; relay 4 81R, completes the pick-up circuits forl relays IZA-Maand,V I2.-HR. It willbe noticed thatu the back; contacts |542 andA |53` of the relays lig-.+8,53 and. 4,-I0R' are provided for the purpose of obtaining an interlocking of theroutes starting from. the. same entrance.

The relay IZTBR is. energized through a circuity includingv wire B f ront contact; I 6 I orA relay SLlefront. Contact |12 of: the relay |2LS,.front contact I3 ot relay BLS, front contactv I4l of relay 1 -8.11%,.Windins of. relay lf2-SR andreturn Wire C4, Inits energized.` condition the relay4 I 2-8R colnpletesthe pick-up circuit of relay tI-1R including wire B, front-` contact 'I of relay BLR, frontcontact I.6 8;Qf relay ILR, front contact 9V of relay ALS, frontcontact I'IIl of relay 8LSfro nt contact; I ;I. of relay 4-8Rfront contact I5 of relay-A-IZR, f ront contact' I (iA oi relay 4-81R,y

front contact4 I1 of relay I2-8R, back contact` I8 of relay 8'II Rb ackf contact I9 of relay 'IWSK, windingv ofu relayAIfIB. and return wire C. The energization of this relay IIHR interrupts at its Contact; 3 6 (Fig. 9) the circuit of the relay 4LS; this-,relay'having strongly delayed release characteristics permits before droppingl with ample allowance the operation of the switch controlrelays IWR5and SWR.,v which will be described furtherbelow. It will also be noticed that the dropping of'v the relay LS ensures thev transfer of thel route relaysyfor example 4-81R, and relays HR, for eXample4`I1.Rto-their stick circuits.

,'Ihe relayAI-IRis-maintained energizedrthrough the-following circuit: Wire B,f1xed resistance 3.5',

- front; contactzll'of relay. 1TB, frontcontact 2| of the-fpullbutton dAnp, front contact 22 of relay 4BR, back contact I9 of 'IWS,Kwndingof the relay 4HR and return wire C. The relay Ill-IR irrite energized.; condition completes? theholdins eircui. of. relay;v 4.-8,1Rz. incl-udine; wire 13.l fixed;

resistance 31,'front contact 23 of relay 4BR, front contact |58 of relay 4-81R, back contact |65 of relay -BR, winding of relay 4-31R and return wire C. The energization of the relay @IHR completes the pick-up circuit of relay lESK which in turn energizes relay IESK (Fig. 8) as in the French patent already referred to, and produces the illumination of the corresponding portion of the track diagram. The energization of relay SHR completes the holding circuit for relay 4-I2R (Fig. 5) including wire B, flXed resistance 35, front contact 22 of relay TTP, front contact 2| of button lAnp, front Contact 22 of relay III-IR, back Contact i3 of relay SHR, front contact I1 of relay |2-5R, front contact I5 of relay 4-81R, front contact I of relay 4-I2R, front contact |52 of relay 4-85R, back contact |53 of relay 8B., winding of relay 4-I2R and return wire C. The energization of relay 4-I2R completes the circuit for energization of relay 3BR. (Fig.1) including wire B, front contact 4I of relay 4-I 2R, winding of relay ERR and return wire C.

The relay IQHR is energized through the following circuit (Fig. 5) Wire B, front contact ISI of relay 5LB, front contact |12 of relay IZLS, front contact |23 of relay SLS, front contact I4 of relay li-81B., back contact 30 of relay SHR, iront contact 3| of relay I2-8R, back contact 29 of relay EWSK, winding of relay I2HR and return wire C. The energization of relay IZHR interrupts at back contact 38 (Fig. 9) the circuit of relay iZLS which has substantially delayed release characteristics, and thus permits with a large allowance the operation of the switch control relay 5WR which will likewise be described further below.

The relay IEHR is held by the following circuit (Fig. 5) Wire B, i'lxed resistance 39, front contact 2d of relay 5T?, front contact 25 of relay 4-81R, iront contact l5 of button 4Anp, back contact 21 of relay Z-SR, front contact 28 of relay IEHR, back contact 29 of relay 5WSK, winding of relay I2HR and return wire C. When energized the relay IHR completes the pick-up circuit of a relay 5ESK which produces illumination of the corresponding section of the track diagram as shown in Figs. 8 and 16, in a manner similar to that already described in the French patent referred to previously. Further, the relay WHR. completes in its energized position the holding circuit of relay I2-8R (Fig. 5) including wire B, Xed resistance 59, front contact 24 of relay ETP, iront contact 25 of relay 1 -81B., front contact 45 of button fiAnp, back contact 21 of 2--8R, front contact 28 of relay I2HR, front contact 3| of relay IZ-iR, back contact 39 of relay 12HR, winding of relay I-SR and return wire C.

The operation of the track: switches to establish this route is effected in the following manner (see Fig. 4) Relay IWR is energized in response to the energization of the relay 4-I2R which established the following circuit: Wire B, front contact 62 or relay 4-I2R, front contact 43 of relay ILR, winding of relay IWR, front contact 4,4 of relay ILR, back contact 45 of relay IB-3NR, back contact 45 of relay 2--i2R, back contact 41 of relay INWS and return wire C. The relay BWR is energized by a circuit including wire B, front contact 4S or" relay BRR, front contact 49 of relay 311B., winding of relay EWR, front contact 55 of relay LR, back contact 5I of relay IB- SNR, back contact 52 of relay 3NWS and return wire C.

The relay 5WR is energized by a circuit including wire B, front contact 53 of relay I2--8R, back contact 54 of relay 5BNR, front contact 55 of relay SLR, winding of relay 5WR, front contact 56 of relay 5LB, back contact 51 of relay SRR, back contact 58 of relay` ERWS, and return wire C.

The operation of the switch indication relays and the arrangements for controlling the signals by these relays are identical With those described in the French patent mentioned before (see Fig. 4). After operation of the track switches, the relays IRWP, 3RWP and 5NW'P are energized and illuminate the corresponding portions of the track diagram asin the patent above mentioned (Fig.

The locking of the track switches is obtained in the following manner (see Fig. 4) The relays ILS and |2LS, which have strongly delayed release characteristics in order to allow the operation of the switches to be initiated, now release and interrupt 'the circuits for relays ILR. and 5LR at the front contacts 59 and 68. When the relay ILR drops, it interrupts the circuit of 3LR at the front contact 6|.

The relays IWR, 3WR and EVV'R are then still maintained energized as in the above mentioned patent by back contacts 43 and 44 of relay ILR, contacts 49 and 50 of relay 3LR, contacts 55 and 56 of relay 5LR. The switches I, 3 and 5 are thus locked while the signals 4 and I2 are still at ustop' It willbe noticed that switch 3 which is not included in the route from 4 to 8 via reversed has been controlled to reverse position so as to protect this route in case the signal Il has been passed without authorization,

It will also be noticed that the voltage of the relays provided with holding circuits such as:

IWR, 3WR, SWR, (Fig. 4)

4I2R, I2-8R, 4-81R, (Fig. 5) is very much higher than normal voltage in order to allow them to be very rapidly energized and then when the holding circuits are established, the voltages are reduced to their normal value owing to the interposition of a suitable resistance in the circuit.

Clearing of the signals 4 and 12.-Relay I2C-r (Fig. 6) is energized through the following circuit: A

Wire B, front contact 62 of relay SLS, back contact 63 of relay SHR., front contact |55 of relay SWR, back contact 64 of relay 5A, back contact 65 of relay B-I2TES, back contact 66 of relay 5LB., front contact 61 of relay 5NWP, front contact 68 of relay I2-8R, back contact 69 of relay 8HR, front contact 19 Vof relay IZHR, front contact 1I of relay 5TP, winding of relay I2G, front contact 12 of relay IZHR. and return Wire C. Relay 4DG is energized over a circuit which is the same as that for relay |2G from terminal B to back contact 69 of relay 8HR, and extends from contact 69 over front contact 13 of relay I2HR, front contact 14 of relay' I2-8R, back contact 15 of relay IA, back contact 16 of relay 2TES, front contact 11 of relay 4-I2R, front contact 18 of relay IRWP, front contact |56 of relay IWR, back Contact 19 of relay ILR, back contact of relay 1A, back contact BI of relay ATES, front contact 82 of relay III-IR, front contact 83 of relay 1TP, front contact 84 of relay ITP, front. contact 85 of relay 4-I2R, winding of relay 4DG, front contact 86 of relay tI-IR, and return Wire C.

Lightingy of the signal lamps and of the corresponding indication Zamps in the traclc diagram-The illumination of the lamps of the signals 4 .and I2 to display clear indications and the display of corresponding indications bythe lamps of indicators 4K and I2K onthe control panel, as a result of the release of relays 4GP and I2GP, (Figs. 18 and 19) the circuits for which are interrupted by the energization of the relays 4DG and I2G, is obtained (see Fig. 15) in a manner corresponding to that described in the French patent referred to. It will be noticed that the block relays for providing caution or distant indications of the signals have `not been illustrated in order to simplify vthe description and the diagramathe operation of `these relays being the usual operation of such relays as ord"` arily utilized in block signalling systems.

Manual cancelling of the route from 4 to 8 via 1 reversed (Fig. 5) .-It may be yassumed-that no train is in the approach locking zone of signal 4. By operating the button 4Anp the signalman interrupts the holding circuits for relays A4-I2R., 4HR., I2-8R, IZHR., which drop.- In dropping, relay 4IIR interrupts at its front contact 23 the holding circuit of the relay 4-81R, which drops. 'Ihe dropping of these relays causes relays 4DG and IZG to drop which control the putting to danger of the signals 4 and I2; at lthe same time the circuits for the signal indicators 4K and I2K are opened and the relay 4-1 A2R :interrupts in dropping the circuit of relay 3RR,which drops likewise. It will be noted that the direction relays (Fig. v8.) fIESK, SESK, IESK are likewise dropped and that `accordingly the track diagram ceases to be illuminated. 'Ihe relays -4I-IR. and 12HR: which have dropped, have reenergized the relays 4LS and IZLS (Fig. 9) which, .0n their part, reenergme the relays 5LB, andV ILR, the 'latter Ieenergizing 3LR.

The track switches I, 3 and 5 are then unlocked but remain in the position assumed, and the signalman may prepare a new route.

In the following the succession of .operations during the passage of a train orzthe like after clearing the signals 4 and I2 will be `described :in the case of the route considered above, that is to say from 4 to 8 via I reversed. It is -eyidentthat although the possibilities of cancelling this route have been described, this ,cancelling has not taken place in the case which will now be considered.

When the train enters the approach section 4T, relay 4TR. is released .and in dropping Causes relay -4AR to drop and the approach section 4AK of the ktrack diagram becomes illuminated in red (Fig. 16).

When the train enters the'iirst section IT of the route relay lTR is released .and inv dropping causes relay *ITP to drop, then, with some delay, relay 'ITZ; relay 'ITP interrupts lat its front contact 83 (Fig. 6) the energizing circuit of relay 4DG which drops and causes Vthe signal'4 to change to its stop ,or danger indication. It will be noticed that the train caused relay ADG to drop, which caused signal 4 to go to danger but independently of Ithis going to danger -the circuit of relay 4BR has been interrupted, the relay ITZ having slow-release characteristics, thus causing relays 4-,I12R and #HR 'to drop, Which interrupt their stick circuits and cancel the route automatically. Relay TTR interrupts the hol-ding circuit of tl'e relays .4-I,2R and 4HR, (Fig. 5) with the same succession in the operation of the relays as that described previously for the manual cancellation, and the track diagram :is dealt with in the same manner as in the patent referred to.. When the -train enters ,sectionV 1 T, the relay I TR drops, releasing relay ,lTP, which in' Vturn releasesv relay ITZ fwth a delay. Relay ITP opens contact 84 in the circuit of the relay 4DG (Fig. 6) to hold that circuit open, the track diagram being governed as in the case of the patent referred to. The relay STR drops in its turn, causing relays STP and 5TZ to release; the relay STPinterrupts the energizing circuit of relay IZG (Fig. 6) at contact 1I, and it also interrupts the holding circuit of the relays I2HR and I2'-8R (Fig. 5) as previously indicated' in Vthe case of manual cancelling. According asv the sections are successively vacated, the operation is the same as in the patent referred to. TheV direction-responsive relays 'IESK, BESK and IESK remain energized until their associated track sec# tions are respectively vacated, to maintain the illumination of the corresponding portions of the track diagram.

A feature of our invention in the provision of means for checkingthat an established route is fully vacated before the opposed signal'is allowed to be cleared. This is accomplished by including a .back `contact of the last direction-responsive relay 'ESK or WSK for the route, in the circuit for the signal control relay HR for'the opposing signal. Y.

For example, in the case of the Vroute from 4 .to 8 vrelay SHR cannotbe energized for clearing the opposing signal 8 until the back Contact 81 of relay 5ESK (Fig. 5) is closed and this'only takes place when a train or the 'like has vacated section 5T (at least when there is no Ymanual cancellation). i Y

Another feature of our invention is the provision of means for locking'the switches inadvance `.of a train in case a signal has been passed Without authorization, no route having been set up. In this case the switches are locked by the relays 3WS, SWS, 'IES (Fig. 10), which control therelays LR as in the patent referred to.

Assuming that the switches have remained in theirposition vassumed during the establishment of theroute 4 to 8 via I reversed after this route has lbeen cancelled and that a train passes the signal 8 when it is .at stop, the relay' 5TP're`- leases and interrupts the pick-up circuit of 5WS (Fig. 10).` The holding circuit of this relay is not established, the relay SESK being in its Vreleased position because no .direction of traiiic is setup. In dropping, relay SWS causes relayl ILR (Fig. 4) to release to lock switches I, switch 3 `is lock-ed :by relay 3 LR which relay is released by relay ILR; switches 5 have been locked bythe dropping of relay SLR the circuitfor which has been interrupted by relay 5TR (Fig. Ll);l l' The establishment .of the route portion from 4 to I2 Will now be described. f The ysignalman having Dressed button 4-I2P (Fig. .5), relay 4-I2R is energized through acircuit including wire B, front contact 1 of relay BLR, ,front contact |68 `of relay ILR, frontcontact 9 of relay ALS, front contact 88 of press button 4 1 2P, back contact vI52 of relay 4-85R, back contact |53 of relay 4-IOR, winding ofv relay l4.I.2R, andk return wire C. The relay 4I-IR is energized over fa .circuit Which is` the same as that J'ust described as far as' and including the front contact 88 of press buttonA 4-I2P, and from contact 88 extend-s over front-contact `I5 of relay 4-l2R, back contact I6 of` relay 4 81R, back contact ,I9 `of relay 1WSK, Winding of relay 4HR andwire C. The holding circuits of the relays AHB. and 4-I 2R are the same as those described for the establishment of the route 4 to 8 via I reversed; the operation vof the track diagram and of the relays 4LS, IWR, ILR, 3RR, 3WR, 3LR, 'IESK and IESK is likewise similar and need not therefore be described in detail.

In the present instance, the circuit closed after locking switches and 3 to energize relay 4DG is slightly different from that previously described (Fig. 6). The circuit now to be'described includes wire B, front contact 89 of relay IZGP, front contact 90 of relay 5WS, back contact 'I4 of relay |2-8R, and thence as previously described for the clearing of the signals 4 and I2, through relay 4DG to wire C,

It will be noticed that in order to avoid deenergization of relay DG during the transfer of its supply from the back contact to the front contact (contact 14 of relay |2-8R) upon the establishment of the route I2 to 8, a holding circuit, (Fig. 6) is established after energization of relay 4DG, which includes: supply wire B, front contact 89 of relay |2GP, front contact 9U of relay SWS, back contact 92 of relay 4-81R, back contact 93 of relay 4GP, back contact 'I5 of relay IA and then over the circuit as previously described for the clearing of signals 4 and |2 through relay 4DG to wire C`. y

The control of the signal lamps (Fig. 18) and the return indication of signal 4 is effected in a manner corresponding to that previously described; also the passage of a train or the like after clearing the signal 4 is eiected under the same conditions as have been previously inentioned for the route 4 to 8 via I reversed.

The establishment of the route portion I2 to 8 will now be described.

The sgnalman having pressed button |2--8P, the relay |2-8R is energized through a circuit (Fig. including supply wire B, front contact |6| of relay 5LB, front contact |'I2 of relay |2LS, front contact I3 of rel-ay 8LS, front contact 9| of press button |2--8P, Winding of relay lZ-BR and return wire C. The circuit for relay IZ-HR extends from wire B over the same path as that for relay |2-8R, as far as and including the front contact 9| of press button |28Pthen passing from contact 9|- through back contact 30 of relay SHR, front contact 3| of relay |2-8R, back contact 29 of relay 5WSK, winding of relay IZHR and return wire C.

The holding circuits of the relays IZHR and I 2--8R are identical with those already described for these relays; the same is the case as regards the operation of the relays IZLS, EWR, BLR, 5ESK and also for the corresponding indications of the track diagram. It will be noticed that after locking the switches 5 (Fig. 6) the circuit for relay I2G is closed as already described for the clearing of the signals 4 and I2. The saine is the case as retards the control of the signal lamps and of the return indication of signal I2, and the effect of the passage of a train or the like when signal I2 has been cleared. It will be observed that for establishing the through route from. 4 to 8 comprising the two routes which are arranged end to end and extend from 4 to I2 and then from I2 to 8, respectively, it is sufficient t0 proceed with the operations by which these two route portions are established, that is, route #1 -8 via reversed may be established by operating button 4-81P alone, or by operating buttons 4-I2P and |2-8P.

As previously mentioned, the apparatus according to the invention is arranged to insure the permanency of certain preferred routes, for example those which are most frequently used.

The term permanent route designates a direct route which when once established will rernain established with successive passages of trains over the route. If a route of this type is to be established from 2 to 3, the signalman presses button 2--8DP of the entrance 2 (Fig. 2) the relay 2-8DR is then energized (Fig. 5) by a c1rcuit including supply wire B, front contact 94 of press button 2-8DP, winding of relay Z-SDR and return wire C. The energization of relay 2-8DR completes the pick-up circuit of relay 2-8R, including supply wire B, front contact IBI lof relay SLR, front contact |62 of relay 2LS, front contact |63 of relay 4LS, front contact 91 of relay Z-SDR, back contact 9S of relay 4-81R, winding of relay 2--8R and return wire C. The energization of relay 2-3R completes the pick-up circuit of relays 2-I2R and 2BR, the former including supply wire B,'front contact |82 of relay ILR, front contact |3 of relay 2LS, front contact |94 of relay BLS, front contact |55 of relay 2-3R, Winding of relay 2|2R and return wire C. The circuit of relay` 2HR is the same as that of relay 2-I2R from wire B as far as and including the front contact |05 of relay 2-8R, and then passes through front contact |96 of relay 2- |2R, front contact |01 of relay Z-BR, front contact |38 of relay |2-8R, back contact |99 of relay SHR, back Contact I II) of relay IWSK, winding of relay 2HR and Vreturn wire C.

The pick-up circuits for relays IZ-BR and IZHR arel also completed by the energization of relay 2-8R; the relay |248R is energized by a circuit including supply wire B, front contact I6I of relay 5-LR, front contact |12 of relay IZL'S, front contact I3 of relay SLS, front contact IUI of relay 2'-8R, winding of relay |2--8R and return wire C. The relay IZHR is energized through the same circuit as relay I2-3R from wire B as far as and including the front contact I0| of relay 2--8R, the circuit for relay IZHR then passing through back contact 39 of relay BHR, front contact 3| of relay |2-8R, back contact 29 of relay 5WSK, winding of relay IZHR, and return wire C.

'Ihe relay 2-8DR establishes its holding circuit (Fig. 5) including: supply wire B, fixed resist-ance I I5, front contact 95 of relay ZI-IR, front contact 96 of relay 2-'8DR, winding of relay Z-BDR and return wire C.

The relay 2-8R establishes its holding circuit including: supply wire B, iixed resistance IIS, front' contact 99 of relay 2ER, front contact |99 of relay 2-8R, back contact 93 of relay 4-81R, winding of relay 2-8R and return wire C. The' holding circuit of relay 2-I2R is as iollows: supply wire B, fixed resistance III, front contact |I2 of relay ITP, front contact |I3 of button 2Anp, front contact I I4 of relay 2HR, back Contact |09 of relay 8HR, front contact |98 of relay |28R, front contact |01 of relay Z-BR, front contact |06 of relay 2-I 2R, winding of relay 2-I2R and return wire C. The holding circuit of relay ZHR is the same as that for relay 2-I 2R from wire B as far as and including front contact I4 of relay ZHR and passes then through back contact I I0 of relay IW SK, winding of relay 2HE and return wire C.

The relay |2-8R establishes its holding circuit as follows: supply wire B, iixed resistance 39, front contact 24 of relay ETP, front contact 21 of relay2-8R, front contact 28 of button ZAnp, front contact 28 of relay IZHR, front contact 3| of relay |2-8R, back contact 39 of relay SHR, winding of relay |2-8R and return wire C.

The holding circuit of relay IZHR is identical with that of relay |2--8R from wire B as far as Iand including front contact'281.of1relayll ZHRiand passes then through back contactZSfn'f :relay WSK, winding of relay IZ-IRandsreturnrwire C.

The resulting operation is similar to .thatlo'f the route previously establishedzfrom I:4 yizo-'z8 1via I reversed considering the relays involved. [txwill be noted briefly: relay -2-I-2R:in its energized Ycondition completes thenormalpickaup circuit of relay IWR (Fig. 4). Relay2|2-`8Rwhenaen ergized completes the Anorrnal.pickeup circuit'iof l5WR (Fig. 4). Then the relay IWRzandNllR are held energized, the track switchesfaremoved and return their indications, thefnormal'indication relays NWP, ENW'P, (Fig. 4) beingenergized.

When relay ZHR is energized,.it energizesrelay IESK, (Fig. 8).

When relays IZHR and fI2-f8R are energized, they complete the pick-up circuit vofrrelay EESK (Fig. 8).

The illumination of the 'track diagramds effected in the manner described in the vlrenchvpatent previously referred to.

When relay 2ER is energized :git 'causes relay 2LS to drop which in turn interrupts'thefcircuit of relay |LR,thus locking switchesfl When relay I-2I-IR is energized it :causes .relay |2LS to drop which inturn,interruptstheicircuit of relay 5LBl and locks switches-5.

The relays 2G and I2G `controlling the clearing of the signals 2 and I2 are `energized (Fig. 1B);

the signal indication relays 2GP:and I2GP;drop to cause the signal indicationsto be `displayed-.on the track diagram as in the previouslyrmentioned French patent.

During the passage of -a train the :signal `.will continue to display a proceed indication, the contacts of relays ITP and 5TP1-in 'the .circuits for relays 2G and I 2G being bridged by the contacts of relay Z-SDR (Fig. 6).

All :the relays involved with zthe vexception -o'f the track relays and track repeaterrelays will remain inactive in their position during the passage of the train.

It will be noted that the automatic cancellation Vof the route does not .take place, :since ithe contacts I|1 and. I8 of relay 2-8DR bridge the contacts I I2 of relay ITP 'and'24 fof .relay LSTP respectively (Fig. 5).V

`In case for example one of the track sections comprised in the considered route is defective, certain rules of safety require a different l:mode of operation for the vestablishment of the route; according to the invention the track switches Ii-ncluded in the defective section are 4then manually controlled from the desk (Fig. 2.) ;by the .buttons NP and RP.

When in the case of the route already described from 4 to 8 via vI reversed, section iIT is defective, the signa'lman after checking the .conkdition of the track as prescribed i-n his regula-V tions and with the object yof insuring lthat it is not occupied, presses in lthis case button IAP (Fig. 3) whereby relay IA (Fig. 11) is energized.

One `will remember that the section .cancelling buttons disposed in a manner already described, are under seal.

The relay IA is energized by the following fcir" cuit: supply Wire B, back contact '|19 of relay 2-l2R, back contact |20 of relay 4|2R, back contact I2I of relay ITP, front .contact |22 of press button IAP, winding vof relay lA'and return wire C.

The relay IA is held energized through the same circuit as is used for its energizationasfar as :and including the back. contact n|121 of relay AITP ,and :passing :then through' the xed `resist ance I.-2:3, frontcontact I|24 of .relay flA, -windin .of relay IA and ereturn wire C.

\When :picking up, .the relay .IA completes the circuit of relay ILR (Fig. 4) by bridging A.withits front .contact |25, the front contact |26 ofthe dr0pped;relay ITR.

.The track switches I being thus unlocked; the signalman'presses the individual control button for :setting switches I toreverse, i. e, IRP, fthus energizing relay IRWS, (Fig. 13') as described in the French patent previously referred to, which relay-is then held energized over its stick circuit and .establishes .a pick-up circuit for relay IWR (Fig. 4') including: supply Wire B, front contact |21 .of relay VI'RWS, back contact 42 of Vrelay 4-^-'|2R, front contact 43 of relay ILR, Wind-ing of relay IWR, front contact 44 of relay ilLR, back .contact 45 of relay IB-3NR, back contact 46 Aof relay Z-IZR, back contact 4'Ir of relay 'INWS nndreturn wire C. The control and indication of switches I is effected as previously described; section IRK of the track diagram is illuminated in xred zby the energization ofthe red lamp for .this `section over the following circuit .(Fig. v1'6'):. Supply Wire B, front contact '|28 of relay. IRWS, vfront contact |29 of relay 'IRWP, front contact |30of1=relay 'ITP, back contact Ii3| :of relay `"ITP, red .lamp .R of section IRK andreturn wireC. The-signalman lnow presses button 81 fof entrancei, whereupon (Fig. 5) the route relay vIl--zillR is energized, `causing the same `sequence .of relay operations with the same consequences :as previously described; however, :relay 'II-:IZR has in picking up, interrupted at its` front `contact (Fig. 11') the holding circuit of relay lA, which .accordingly drops; .the relay -4DG controlling the clearing of vthe vsignal is however, not energized, its circuit which has already been .described being interrupted at 'the front Contact S4-.of relay yITP (Fig. .6)

.It will belnoticed (Fig. '5) in reference tothe pick-up circuitsfor relays 4|2R and '4HR, :the relay IIR, which is released by the dropping of relay IA would, by dropping, prevent theseftvvo relays from being energized; the front contact |68 of .relay I'LR. 'is however, bridged by lfront contact |32 :of the yenergized relay lRWP.

`Signal I2 will go to proceed (relay IZHR energized) and the operation is identical with that described in the previous example; signal 4 however, will not go to proceedj contact r82| of relay 'ITP `in the circuit for relay DG being open, but it may be passed at danger by the issue of Ya permit at the block station. On the other hand, if the signal involved is one governing movements over a permanent route, the contact of' the involved track relay may be bridged by a Contact ofthe relay DR. for direct passage; or a call-on indication may be given'if the signal 'is accordingly arranged. It will also be noticed that when a section is defective the direction-responsive relay involved (I ESK) does not drop (Fig. '8), as it is heldenergized by the back contact 280 of the track relay ITP of the section. It will be noticed that at this time the corresponding portion of .thev track diagram will for' that :reason remain illuminated; for extinguishing its illumination it is only necessary for theksignalman to press again on the panel of Fig. 3 the section cancelling button, in the present case button IAP, which on its part energizes cancelling relay IA (Fig. 11) which, at its back contact 20|, interrupts the holding circuit vof the direction-responsive relay IESK (Fig, 8); the signalman then reestablishes the route by operating the press button 8l of entrance 4 for causing the cancelling relay |A to drop, and then he cancels the route by operating button 45mg) (Fig. 2).

The invention also relates to arrangements permitting a call-on operation; these arrangements will be described hereinafter considering by way of example, the cas'e in which the route from 4 to Iii has been established and cancelled by a train stopped in a position in which it fouls the circuits 'FT and 3T.

In order to give the call-on indication, the signalman proceeds in the following manner; he establishes once more the route from 4 to by pressing button IB of entrance 4. Relay 4|0R is thereby energized, also relay lil-IR, producing the same operations as have already been described except as regards the holding circuit, which is somewhat different, since both the track relay 1TP and the relay 'ITZ are dropped; accordingly the circuit will include: supply wire B, resistance 35, back contact |33 of relay '|TZ (Fig. 5), front contact 2| of button 4mm, front contact 22 of relay 4HR, back contact |9 of relay 1WSK, winding of relay GHR and return wire C, and, in respect to relay 4-lilR, from iront contact 22 of relay 4HR to front contact 252 of relay 4|0R, back contact 253 of relay IGI-IR, back contact 264 of relay 4-85R, back contact 205 of relay 4-|2R, winding of relay 4|GR and return wire C. The signalman then presses button 4CP when the train arrives at the signal 4 which stands at danger; the relay 4COS is energized through the following circuit (Fig. 14): supply wire B, fro-nt contact |34 of press button 4CP, front contact |35 of relay 4G?, back contact |36 of relay 4AR, winding of relay 4COS, and return Wire C.

The holding circuit for 4COS includes (Fig. 14): supply wire B, front contact |31 of relay 4HR, front contact |33 of relay 4COS, front contact |35 of relay 4GP, back contact |35 of relay 4AR, winding of relay 4COS and return wire C.

The relay 4COS completes in its picked-up condition the circuit of relay GLM (Fig. 6) including: supply wire B, front contact |39 of relay |0LS, back contact |45 of relay IBHR, front contact |5'| of relay 5WR, back contact |4| of relay BLR, front contact |42 of relay ENWP, front contact |43 of relay EBNR, front contact |58 of relay 3WR, back contact |44 of relay 6|0TES, back contact |45 of relay 3A, back contact |46 of relay 3LR, front icontact |41 of relay SNWP, front contact |48 of relay IWB-SNR, iront contact |49 of relay INWP, front contact |56 of relay IWR, back contact 'i8 of relay ILR, back contact Si) of relay 1A, back contact 8| of relay 4TES, front contact 82 of relay 4BR, front contact |50 of relay 5GP, front contact |5| of relay 4COS, winding of relay 4LM, front contact 85 of relay lll-IR and return wire C.

The energization of relay ALM causes the call-on indication to be displayed on signal 4 (Fig. 18). Relay 4LP/IP drops (Fig. 19) and gives fil the return indication on the track diagram by Y lighting lamp G of 4K (Fig. 15), which will display a flashing light owing to its being supplied through the contact of the asher relay CT.

The train then passes signal 4 and when the last axle has cleared the approach section, relay 4AR is reenergized and causes relay 4COS to drop which, on its part, causes relay ILM (Fig. 6)

to drop; the signal will then go to danger thus protecting the last train.

It should be noticed that one may provide additional safety arrangements by interposing in the approach section, which is of substantial length, an additional track section adjacent the signal 4, this section which may be of short length will be provided with a protection relay Whose contacts are interposed in the holding circuit of relay 4COS. According to a modification of this arrangement a track instrument or its equivalent may be used, arrangements of this type replacing the previously described circuit of reliay 4AR.

As a safeguard against faulty operation which would result from simultaneously pressing a number of route buttons associated to the same entrance, an interlocking between the involved route relays is provided according to the inven- .tion (Fig. 5).

For example, in the pick-up circuit of relay 4|2R and in its holding circuit back contacts |52 and |53 of relays 4-85R and 4|EBR are inserted, which will prevent the energization of relay 4-|`2R when either of the relays 4-85R or 4|0R are energized by mistake.

This protective system may be used in a small installation; in a more important one it would, however, be cumbersome owing to the great number of contacts involved.

Fig. 5A shows a modified arrangement which obtains this interlocking in a simple manner by giving priority to the energized holding circuits of certain routes diverging from the saine entrance.

If, for example, route 4|Z is to be established, the relays 485R and 4|0R must be in their released position.

In the circuits of Fig. 5A, the relay 4||JR insures by its contact |54, priority to the route 4|0 relative to the routes 4--8 via 5 reversed and 4|2 via reversed.`

It will be noticed that the circuits oi the relays 2-8R, 4-81R, 2-8DR and Iii-4DR, which are identical with those illustrated in and described with reference to Fig. 5, are not shown in Fig. 5A, although their provision would be necessary.

The protection against faulty operation as a result of simultaneously pressing two vcontrol buttons for routes which are incompatible by involving different positions of the same track switch, for example by pressing simultaneously the buttons 8-6P and Ill-5P, is obtained by including in the signal circuits controlled by the corresponding relays HR (Fig. 6), for example, as illustrated for the relay 8HR or MEHR, a neutral front contact of a relay WR, in this case the contact |51 or |55 of relay SWR, which interrupts all the circuits for the involved routes.

Relay SWR is dropped in this case, in which two route buttons have been pressed for routes that are incompatible by involving different positions of the same switch, for the reason that both its terminals are supplied with one and the same polarity, thus rendering energization impossible.

It will also be noticed that additional protection is provided by the relays 5NWP and SRWP, which cannot be energized simultaneously.

It is thus necessary for the signalrnan to cancel these two routes 8 to 6 and 0 to 6 before he is able to establish a new route. It will further be noted that if a route button is pressed after the dropping of relay LR, that is to say, about one second after the operation of a conflicting route button, this second operation will be without consequence, since the relay LR interrupts the current supply of the route button, that is', in the case rpreviously referred to, the circuit for the routerelays G-SR. or li--IURl is opened at coleitact 206 or 207 of relay BLR (Fig. 5).

lIn'Fig. 5B, another arrangement according tov the invention is illustrated which permits the route relay provided with two windings to be replaced'by an ordinary relay. Y

The example illustrated relates particularly to the circuits for the route relay 648B., but itwill be apparent that similar circuits may be provided forany of the press buttons.y v' A FigQ'lZon the one hand, andthe "description" of the ysup-ply circuits herein illustrated on the other hand, will showY that the normal ener-giga.- tiorfof a relay R, for producing an addition of the fluxes ofthe two windings inthe I'nagneticy cir cuit (not illustrated) of theseA relays R,is. nly

possible when' the' common/rerum 'circuit je;

wards C`is undamaged. When for any reason,f

rection of tramo movement over the route.' .For

example, operation of button 6-8P I(Fig.y 513)` produces the energizationv of relayY through: supply wire B, front Contact 1 of relay SLR', front contact 206 of rel'ay'SLR, front con;

tact2l0 oi relay GLS, front contact y2,|| ofrellay LS, trontcontact 2|2 of press buttonf6L+8JP,I windingoy relay 6-'0R, and return wire C. The energizing' circuit ofY relay GHR is the. same as the circui't'justdescribec as far as th'frbnt com ci-,Q 2Hf`of relay LS and tlf-len extends4 V'over iront. contact 2|3 of thepress buttontfBP., fronti contact v2|ll of rela'y li-tPgbacl: contact 2|'5'lof relay 6HR,'back contact 2|6 of relay"'3.f-K, winding of relay SHR to the return wire C.

The holding circuits of these'two relays pass for relay SHR, from lsupply wire B through frontv contact 2H' of relay BTP, iront contact ,2|8of button 6AM), front contact 2|9 of relay B HR, back Contact 2| 6 of relay SWSK,v winding of relay SHR, and return wire C; for'relay (iT-"8B, from' supply wire B through back vcontact (22,0 of rfelay SHR., front Contact 22| f relay SHR, iront contact222 of 'relay 6--8R, windingof relay (vi-SRI and retur'n'wire C. Likewise, it is siif cient for establishing a route in the l )p'pds'ite direction to press button 8-6P,whose`cir c'uit,

being symmetrical to that described above exceptv for :the energization of relay SHR instead ofy relay 6HR, need not be described detail. f y As regards the operation of the track diagram referred to above 'it would be ofadvantage ton reduce as much as possible the spacereqiired bythe illuminating elements while` 'still assuring',

uniform and intensive illumination, and to facilitatethe replacement of thesourcesfolf1 light with?` out necessitating any interference with the wir-A ing proper. With this object in View theinven-V tion provides a particularly advantageous arfrangement which is illustrated ,in a secti'onfalong a ver-tical" plane at right angles tovtheffront surfeur@` of the track diagram in Fis. 29, and. 11.1 a corresponding sectional plan view in Fig. 2l.

As Vshown in 'these iigures, lamps of small dimensions'` are used, which are mounted in a socketthe' contacts of which are of the type with concentric, locking. lFurthermore, the single faces of vslixght'inclination and of a certain length The-lamps and their connections are entirely @Ommo'return'cohnection through the bedr Qf the' socket has been replaced by individual wire terminals which may be grouped according te circuit conditions. Finally two reflecting surare used'owing to which Ithe light rays issuing from the source are successively reflected, which increases the output. This unit is so arranged that all the active parts are accommodated between the panel in front of the socket and an insulatingpanel 'parallel'theretd and the connections'may be made at the rear of the latter panel.

As .shown in the drawings, the lamps 30| and 302 are of the vtype having a screw base of the M kind usually employed in ashlights, that is to say, are of very small dimensions, and are inserted in the base of the reflector which has a quadrangular cross section, and is formed with l the reecting surfaces 303 and 404 carried :by the -f front lpanel 301 of the track diagram at both sides of the opening 306 of this panel. This opening is covered by a translucent screen 305 extending along the opening 306 of the panel 301. The lamps 30| and 302 Aor only one of them may .be accommodated in vcolored caps 308 of translucent material which are carried by the reflector 303, v304 in order to insure when necessary illumination of the strip 305 in a different color (for example red).

supported by Ithe insulating panel 3|0 which extends parallel tothe panel 301 and is provided withopenings accommodating the iixed sleeves 3| Ii; in these sleeves plugs 3|2 of insulating material may be mounted which are provided at their rear end with a moulded flange 3|3 and attheir front endwith a metallic receptacle 3|4 provided with screwl threads corresponding to those of the lamps v30| and 302, and which is in contact with the' truncated conical slotted front end Vof the iixed sleeve 3| On vthe rear surface of the panel 3|0 metallic strips 3|5 are mountedr which form bus-bars which are provided with spaced holes; these holes may accommodate connector plugs 3|6 which are connected to vflexible cable 3|'| which in turn is connected with the central contact 3|8 Aof the removable plug 3|2. On the opposite surface of the panel 3|0, that is to say, at its inner surface,

conductor: elements 3|9 are' secured by means of screws- 320 and the portion of these conductor elementswhich is in contact with the sleeve 3| |k is recessed witha curvature corresponding to the external shape of this sleeve. Under the nuts of the screws 320 a terminal connector 32| is h eld through which current is supplied'to theF fixed sleeve according to the wiring asrequired, and which constitutes one of the terminals 'for the energiza-tion of the lamp.

Y It will .be'seen that the removable plug carrying .the lampmay be pulled out to the rear of the insulatingpanel, aftertaking out the connector plug 3|6 from the bus-bar 3|5 which constitutes the other terminal. l

'The slots ,in'sleeve 3| are arranged to be compressed to insure holding the removable plug iny place with the sleeve'in contact with the metal piece 3|4v -It will be seen that current arriving fromv'one of' the terminals through the bar 3|5 is conducted by means of the connector plug 3|6 and the cable 3H to the central contact pin 318 and to` the central contact of the lamp and returns from the latter through parts 3M, 3| I, 319 and'32i) to the other terminal 32l.

Although we have herein shown and described but one form of apparatus embodying our invention and two modications thereof, it will be understood that various changes and modifications may be made therein without departing from the spirit and scope of our invention.

Having thus described our invention, what We claim is:

l. In an interlocking control system for a track layout comprising a plurality of track sections interconnected by track switches to form 'different traffic routes, with signals at the entrances to such routes, a control panel comprising a track diagram adapted to form illuminated representationsfof the different trai-lic routes, a control desk associated therewith provided with a group of buttons for each route entrance, each group including a route button for each route diverging from the corresponding entrance, each such button being marked to identify it according to the exit end of the route with which it is associated, route control apparatus responsive to the momentary operation of any one of said buttons alone, to initiate a sequence of operations comprising the automatic operation of the track switches as required to establish the corresponding route, the clearing of the signal at the entrance to such route when established, and the illumination of the portions of said track diagram representing said route; and means controlled automatically by a train passing over said route in `response to the clearing of said signal for cancelling said route section by section and for cancelling the illumination of the corresponding sections of the track diagram to indicate the progress of the train over said route.

2. In an interlocking control system for a track layout having a plurality of track switches adapted to be interconnected to form different traffic routes with signals at the entrances to said routes for governing trafc movements in opposite directions, a route relay for eachroute, a signal control relay for each signal, an individual route button for each direction for each route, a route circuit network including a circuit for veach direction for each route relay, each closed in response to the momentaryoperation of the corresponding route button alone,` for successively energizing the route relay for such route and the signal control relay for the signal which governs traffic movements over the route in the corresponding direction, switch control relays controlled by the lenergized route relay for operating the track switches as required lto establish the corresponding route, a circuit controlled by the energized signal control relay closed only when each switch of such route is in the position which the route requires, for clearing the associated signal to permit a trafc movement over the route, and means controlledrby a train entering s uch route for releasing the energized route and signal control relays to cancel the route.

3. In an interlocking control system for a track layout comprising a plurality of track sections interconnected by track switches to form different traflic routes certain of which are arrangedv end-to-end to form portions of a through route, a control desk provided with a group of route buttons for each route entrance, each group including va button for each route diverging from the corresponding entrance, route control apparatus responsive to the operation of any route button alone to initiate a sequence of operations comprising the automatic operation of the track switches as required to establish the corresponding route or route portion, said apparatus being responsive to the operation of the route button for said through route to establish each portion thereof, and means controlled by a train occupying any section of a route for cancelling the corresponding section only of such route.

4. In an interlocking control system for a track layout comprising a plurality of track sections interconnected by track switches to form dierent traiiic routes certain of which are arranged end-to-end to form portions of a through route, with signals at the entrances to said routes, a route relay for each route including one for said through route and one for each route constituting a portion thereof, a signal control relay for each signal, an individual route button for each route including one for said through route and one for each route constituting a portion thereof, a route circuit network including circuits for each route closed in response to the momentary operation of the corresponding route button alone, for energizing the route relay for such route, a circuit closed by each energized route relay except the one for said through route for energizing the signal control relay for the signal at the entrance to such route, circuits closed by the energized route relay for said through route for successively energizing the route relay and signal control relay for each portion of said through route, switch control relays controlled by each energized route relay except the one for said through route for operating the track switches as required to establish the corresponding route, a circuit controlled by each energized signal control relay closed only when each switch assumes the position required for the route to clear the associated signal, and track controlled means responsive to a train entering the rst section of a route for releasing the corresponding route and signal control relays.

5. In an interlocking control system for a track layout comprising a plurality of interconnected track switches adapted to form different traffic routes certain of which are arranged end-to-end to form portions of a through route, a control desk provided with a group of buttons for each route entrance, each group including one or more route buttons and a single cancelling button, there being a route button for each route diverging from the corresponding entrance, route contro1 apparatus responsive to the momentary operation of any route button alone to initiate a sequence of operations comprising the automatic operation of the track switches as required to establish the corresponding route or route portion, said apparatus being responsive to the operation of the route button for said through route to establish each portion thereof, means responsive to the subsequent operation of the cancelling button in a. group containing a route button which has been operated for cancelling the corresponding route or route portion, the cancelling button in the groupfor the entrance to said through route being effective to cancel either the entire through route or its rst portion only, dependent upon whetherthe through route button or the button for said rst portion has been operated.

6. In an interlocking control system for a track layout having a plurality of track sections includ- 

